Andrea Palermo’s life has taken on the ups and downs of the tides she follows on her phone app.

As a resident of a back bay neighborhood on a New Jersey barrier island, she has no choice but to track the wind, weather and moon phases, and be ready to change plans in an instant.

During storms, and sometimes under clear skies when high tides coincide with full moons, the bay water rises over the marshes, crosses neighbors’ properties, runs down her street and floods her yard.

It still threatens her cars, but will never get into her house again. After Hurricane Sandy, which flooded her first floor, she got a grant to raise the home 12 feet. Now, she walks up 18 stairs to get to the front door in her Merion Park neighborhood near the 34th Street bridge.

Facing strong opposition from climate-change groups, Miami on Thursday backed down from a change critics said would undermine the city’s quest to position itself as the shining example of how a city should prepare for climate change.

Multiple commissioners and a host of activists were worried a change to the city’s leadership structure could send the public and other governments the wrong message about how seriously the city is taking climate change. They feared that high-level planning decisions and big-ticket projects across the city wouldn’t get the necessary input from the staffers with expertise.

Core samples, tide gauge readings, and, most recently, satellite measurements tell us that over the past century, the Global Mean Sea Level (GMSL) has risen by 4 to 8 inches (10 to 20 centimeters). However, the annual rate of rise over the past 20 years has been 0.13 inches (3.2 millimeters) a year, roughly twice the average speed of the preceding 80 years.

Over the past century, the burning of fossil fuels and other human and natural activities has released enormous amounts of heat-trapping gases into the atmosphere. These emissions have caused the Earth’s surface temperature to rise, and the oceans absorb about 80 percent of this additional heat.

The rise in sea levels is linked to three primary factors, all induced by this ongoing global climate change.

That’s just what you can do with EarthTime, a new online tool that blends satellite photos of Earth with data from university research programs, government agencies, and nongovernmental organizations to create eye-popping animations showing how seas rise in tandem with temperatures to swallow up low-lying areas.

It’s not a pretty picture.

“Sea level rise is a profound threat,” Michael Mann, director of the Penn State Earth System Science Center and a noted expert on the effects of climate change, told NBC News MACH in an email. “Globally, as many as 650 million people live on land that will be submerged or exposed to chronic flooding by 2100 given business-as-usual burning of fossil fuels and sea level rise of 6-8 feet.”

If Floridians residing in coastal communities presume sea level rise is a turn-of-the-century problem for future generations, a group of scientists is delivering a weather forecast they may consider unsettling.

Five Florida communities — Cape Sable (the southern point of the peninsula), Key Biscayne, Key West, the Lower Keys and the Middle Keys — could experience recurring tidal flooding unrelated to any storm events by 2035, according to their study. Three of those locations — Cape Sable, the Lower Keys and Middle Keys — already find themselves partially submerged at times but the forecast says their frequently inundated areas will roughly double in size within the next 17 years.

Under the Union of Concerned Scientists’ fastest sea level rise scenario, 13 more communities could be added to that list by 2045 — including Merritt Island, Miami Beach, Ponte Vedra and St. Pete Beach. By that year, the group reports, 60 percent of the Lower Keys, 39 percent of the Middle Keys and 38 percent of Key West could find themselves underwater for about half of the year.

By 2060, under this “high scenario,” that number of Florida communities expands to 32 — including Cocoa Beach-Cape Canaveral, Fort Lauderdale, Jacksonville Beaches, Longboat Key and Palmetto.

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The Invading Sea is a collaboration by the editorial boards of the South Florida Sun Sentinel, Miami Herald and Palm Beach Post —
with reporting by WLRN Public Media —
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